In farming operations, especially when planting seeds for crops, it is the usual custom to precondition the soil of the field by advancing any number of known power driven machines over the field in order to break up the sod or soil and prepare the field for the implanting of seeds.
After the field has been pre-conditioned, automatic seed planting machines may be used wherein the automatic seed planting machines are advanced over the field and, when advancing over the field, first, create a furrow in the pre-conditioned soil; second, automatically distribute seeds in the open furrows; and, finally, cover the seeds by refilling the furrow with soil.
Generally, such automatic seeding machines have a power driven rotary steel disc that is adjustably positioned so as to engage the field surface and open a furrow in the field as the machine advances along over the field. This power driven rotary steel disc usually rotates in the direction of travel of the advancing machine and, being adjustable, may create a furrow to any desired depth, the usual depth of a furrow being up to about three inches deep. When such a power driven rotary steel disc is used in a pre-conditioned field, the performance of the steel disc and the tool life of the steel disc have been found quite satisfactory.
Automatic seeding machines, however, are also used in a number of situations where pre-conditioning the soil which is not desirable, for instance, in planting further seeds in an already existing pasture for livestock. When planting seeds in an already existing pasture, it is desirable to disturb only the soil necessary for the planting of the additional seeds while being careful not to disturb to any great extent the already existing vegetation in the pasture.
Other examples of situations where preconditioning of the soil would not be desirable would include the planting of seeds on hillside fields where, if too much soil is loosened, there is a danger of the fertile top soil being carried away by adverse weather conditions, such as high winds and heavy rains.
When the automatic seeding machines must work in circumstances where soil has not been preconditioned for the planting of the seeds, the steel disc used to open the furrows must operate under extremely harsh conditions. The steel disc must rip through solid soil, sod, imbedded rock and stubble, and other foreign material which is usually imbedded and held in place within the solid soil. Such harsh conditions are very abrasive upon the steel discs and significantly shorten the tool life of the discs and limit the effectiveness of the automatic seed planting machine.
It is an object of the present invention to provide a disc for use on an automatic seed planting machine that will have an extremely long tool life when used in abrasive soil conditions.
It is a further object of the present invention to provide discs having replaceable wear elements distributed around the periphery of the disc such that the discs, themselves, may be repaired when the bit elements become worn.
It is a further object of the present invention to lessen the down time for repair of such discs in an automatic seeding machine.
It is a further object of the present invention to provide a disc that, while having a significantly longer tool life than discs of the prior art, is still economically efficient when used upon such automatic seeding machines.